Humidity consistency for halmahera

[Will79]

We recently acquired a 3-4 year old Halmahera about a week ago, and we are housing him in a 75 gallon tank. He was well cared for and seems to be in good health besides being a little nervous as he is staying burrowed most of the time. Despite this he has already eaten and the only problem we are having so far is humidity consistency. We live in a high desert and our house is very arid. We have a screen lid for him and it is covered a little over half way with tinfoil. We also have a humidifier on a cycle, going on every ten minutes for five minutes at full blast. Every time the humidifier goes on, the humidity spikes up to around 95%, but once it goes off, it drops to 60% and below by the time it comes back on. I have read that they are meant to be kept at no less than 60% with 80-100% being ideal. My question is, how much fog is too much fog? When the fogger runs, the cage becomes very cloudy and I’m concerned that it is unhealthy for him. Should I increase the time the fogger goes and limit the time in between or will that be uncomfortable/harmful for him?

I’ve also heard about humidistats and, though they are a bit pricey, Im willing to get one if they work well with humidifiers. (I also should mention that I am not having nearly as big of a problem keeping humidity high enough at night when his heat lamp turns off). I have been cautious with misting as I am afraid I may over saturate the substrate and create a entirely different problem for him, however the humidity does stay more consistent after misting for longer.